1. Technical Field
Example embodiments of the present invention relate in general to a transmission method using a multi-input multi-output (MIMO) antenna system in a third generation partnership project (3GPP) long term evolution (LTE) uplink, and more specifically to a method of transmitting control information, such as ACK/NACK information, a channel quality indicator (CQI)/precoding matrix indicator (PMI), and a rank indicator (RI), using a physical uplink shared channel (PUSCH) region in a MIMO antenna system.
2. Related Art
FIG. 1 shows a time-frequency resource grid when control information is transmitted using one layer and a PUSCH region according to 3GPP technical specification (TS) 36.211 V.8.6.0.
In other words, FIG. 1 illustrates a method defined in 3GPP TS 36.211 V.8.6.0, that is, resource arrangements in a region 102 for transmitting a CQI and a PMI, a region 105 for transmitting ACK/NACK information, and a region 104 for transmitting an RI through a PUSCH region.
FIG. 1 shows a structure of one resource block (RB) or a plurality of RBs, in which 14 symbols are transmitted in one sub-frame in the time domain, when a normal cyclic prefix (CP) is used. Even when an extended CP is used, a structure similar to this structure is obtained. Thus, only the case in which the normal CP is used is described for convenience, but the description can also be applied similarly when the extended CP is used.
Although symbols in the time domain are referred to by various names such as an orthogonal frequency division multiplexing (OFDM) symbol, a single carrier frequency division multiple access (SC-FDMA) symbol, a discrete Fourier transform (DFT)-spread OFDM symbol, and a DFT-precoded OFDM symbol, the symbols are referred to as OFDM symbols for convenience in example embodiments of the present invention.
Referring to FIG. 1, in the fourth OFDM symbol section of each slot, a reference signal (RS) 101 is transmitted using all frequency resources in allocated RBs, and a CQI/PMI 102 is transmitted using frequency resources disposed at an uppermost region.
Also, ACK/NACK information is transmitted in a lowermost region opposite to a frequency used by the CQI/PMI using the third and fifth OFDM symbols 105 of each slot. An RI is transmitted in the lowermost region opposite to the frequency used by the CQI/PMI using the second and sixth OFDM symbols 104 of each slot.
In 3GPP TS 36.211 V.8.6.0, only a method of transmitting control information using one layer and a part of a PUSCH region is specified. However, in next generation mobile communication technology such as LTE-advanced, which is the next version of LTE, standardization is underway to enable PUSCH transmission using a plurality of layers. In preparation for PUSCH transmission using a plurality of layers, a new standard for a method of transmitting control information in a PUSCH region is required.